Update help files

Benno Schulenberg suggested some changes to the help messages
to provide some consistency and clarity for both the users and
translators of procps.

The test needed to be updated as the pmap output changed too.

Signed-off-by: Craig Small <csmall@enc.com.au>

pmap.c

@@ -106,7 +106,7 @@ usage(FILE * out)
 {
 	fputs(USAGE_HEADER, out);
 	fprintf(out,
-		_(" %s [options] pid [pid ...]\n"), program_invocation_short_name);
+		_(" %s [options] PID [PID ...]\n"), program_invocation_short_name);
 	fputs(USAGE_OPTIONS, out);
 	fputs(_(" -x, --extended              show details\n"), out);
 	fputs(_(" -X                          show even more details\n"), out);